Transcranial magnetic stimulation (TMS) uses a powerful electromagnet to induce changes in the neuron's electrical patterns. The researchers administered TMS to 16 healthy adults for five days, by staggering the sessions of two seconds with breaks in between. They were monitored by MRI and given memory tests, reports Newsweek.

According to the team, the subjects do not feel more than a light tap on their head during the TMS.

The memory power improved with the electrical stimulation though not extraordinarily. But more importantly, the researchers found that by stimulating one area in the network, the connected regions improved in their contribution to brain functioning and memory.

"This memory network that we targeted has been shown to be impaired in a variety of disorders," said lead investigator, Joel Voss, assistant professor of medical social sciences at Northwestern University Feinberg School of Medicine.

The study goes to show how memory does not lie in the hippocampus alone, but in the network of regions.

The researchers began by figuring out which outer regions of the brain worked with the main memory structure, the hippocampus, and then tested the treatment on these areas like the lateral parietal cortex. The MRIs on the 16 individuals first mapped the brain's memory network and the associated cognitive functions.

The tests conducted were on healthy individuals but the team will soon conduct the same TMS experiment on older adults, suffering from age-related memory decline and early stages of Alzheimer's disease.

The treatment has dramatic implications for memory-impaired individuals with no effective treatments for these conditions.